分解因式: ①(x+y)2-9y2 ②5ab2-10ab+5a.
问题描述:
分解因式:
①(x+y)2-9y2
②5ab2-10ab+5a.
答
①(x+y)2-9y2
=(x+y+3y)(x+y-3y)
=(x+4y)(x-2y);
②5ab2-10ab+5a
=5a(b2-2b+1)
=5a(b-1)2.